Haptoglobin (Hp) is a protein produced predominately by the liver . In humans two types of genes for Hp exist (1 and 2) with possible combinations of these two genes- 1-1, 1-2, or 2-2. The Hp 2 gene is believed to have arisen from the Hp 1 gene in human evolution. Subsequently the prevalence of the Hp 2 allele has spread throughout the world, probably as a result of its ability to provide a selective advantage against infectious disease. The Hp 1-2 combination is a very common one. In most western countries, the prevalence of the Hp genotypes is 16% Hp 1-1, 36% Hp 2-2 and 48% Hp 2-1.